The fireworks industry has employed black powder-based pyrotechnic compositions in both stationary and projectile forms in the past to produce various different types of pyrotechnic displays. One common pyrotechnic that is used in pyrotechnic displays is a “gerb.”
As known in the art, a gerb is a tube that is sealed at one end, has a nozzle at the other end and is filled with a pyrotechnic mixture containing at least an oxidant and a fuel. A gerb is somewhat similar to a rocket, providing a pyrotechnic effect that is similar to a vertical spray or fountain of flame, sparks or stars. However, unlike a rocket, a gerb is typically used as a stationary portion of a set piece and does not move. As is known, the nozzle, choke or restriction portion of the gerb increases the internal pressure to give more height to the spray of sparks and flame and to generally improve the burning efficiency of the pyrotechnic mixture. Gerbs typically include a clay nozzle with a prime situated adjacent the clay nozzle and in contact with an ignition source, such as an electric match, located within the nozzle opening. Other gerb structures are, of course, known and available in the marketplace.
In the past, gerbs typically have been used in stationary platforms to send sparks and flames upwardly from 5 to 45 feet and for short durations (e.g., less than thirty seconds). Although gerbs are generally used as stationary portions of set pieces, a specialized gerb known as a driver is used to provide motive force to a moving portion of a set piece, for example a wheel rotating in a vertical plane, such as a Catherine wheel or flying saucer. Such wheels and rotating pieces rely on an arrangement of gerbs, for example, three drivers arcuately separated from each other by one hundred twenty degrees about the wheel perimeter, to give sufficient motive force to turn the wheel, thereby providing a ring of fire visual effect.
While gerbs are commonly available and generally inexpensive, the range of pyrotechnic displays currently achievable with gerbs is fairly limited. Therefore, if a method and system were provided to substantially increase the range of visual effects achievable with gerbs, an important contribution to the art would be at hand.